The invention relates to methods for authenticating objects, and in particular, relates to methods for embedding security data into products, and methods for authenticating these products using the embedded security data.
Counterfeiting and piracy have a huge economic impact. While numerous product security features have been developed, there remains a demand for cost effective security measures that inhibit counterfeiting and piracy.
Research in the field of steganography (also called xe2x80x9cdata hidingxe2x80x9d) offers promising technology for combating counterfeiting and piracy. One form of steganography is referred to in popular literature as digital watermarking. Digital watermarking is a process for modifying a host signal or object to embed a machine-readable code into the host. The host may be modified such that the embedded code is imperceptible or nearly imperceptible to the ordinary observer upon viewing or playback, yet may be detected through an automated detection process.
Most commonly, digital watermarking is applied to media such as images, audio signals, and video signals. However, it may also be applied to other types of media, including documents (e.g., through subtle line, word or character shifting), software, multi-dimensional graphics models, and surface textures of objects.
The invention relates to methods for authenticating products using embedded security data in the product. One aspect of the invention is a method of making a secure product using data hidden in the product itself. This method assigns a product identifier to the product, such as a unique serial number. It also steganographically embeds security data into the product. The security data includes the product identifier (e.g., a hashed version of it). The security data is embedded such that it is machine readable and enables automated authentication of the product by comparing the security data decoded from the product with the product identifier.
Another aspect of the invention is a method of authenticating a product using embedded security data. This method receives a product identifier associated with the product, and decodes security data steganographically embedded into the product. It then validates the product by comparing the decoded security data with the product identifier.
Another aspect of the invention is a product that includes security data steganographically embedded into it. The product is assigned a product identifier that is related to the security data. The relationship between the product identifier is defined such that authenticity of the product may be evaluated by comparing the security data decoded from the product with the product identifier.
In this document, the term xe2x80x9cproductxe2x80x9d broadly encompasses physical objects (e.g., goods), and other objects associated with them like packaging, tags, labels, documentation, and media supplied on, by, or with the object. Within this broad product context, the embedding process may encode security data on any of these types of products. To determine whether a product is authentic, the methods and systems described in this document can be used to evaluate security data embedded on the product itself, its packaging, labels, tags, media, etc.
One implementation of these methods and secure products employs a form of steganography referred to as digital watermarking. However, other forms of steganography may be used as well. Further features will become apparent with reference to the following detailed description and accompanying drawings.